Well-drilling apparatus



Nov. 21, 1950 H. L. FEASTER WELL DRILLING APPARATUS Z-Sheets-Sheet 1 Filed June 2. 1947 f! l N FE ER DRILLING APPARATUS N ov. 21, 195o Harig L. feas ier Patented Nov. 21, 1915 UNITED STATES PATENT OFFICE WELL-DRILLING APPARATUS Harry L. Feaster, Artesia, Colo.

Application June 2, 1947, Serial No. 751,833

(Cl. Z55-45.8)

4 Claims.

This invention relates generally to well drilling and is directed Particularly to the method of drilling by lowering a drill operating motor to the bottom of the drill casing so that the motive power for the drill bit is applied directly at the bit.

An object of the present invention is to provide, in rotary drilling, a drilling unit at the bottom of the drill hole, operated by electric power delivered directly thereto, and including a relatively long motor having a hollow armature shaft through which the drilling mud may be delivered directly to the drill bit.

Another object of the invention is to provide a motor for operating a drilling bit in the bottom of a well hole, which is constructed so that several such motors may be directly coupled tgether where it may be desirable to increase the power applied to the drill bit.

Still another object of the invention is to provide a well drilling system wherein the drill bit operating motor is carried at the lower end oi the drill pipe line, with novel means for carrying electric current along the pipe line to the drill motor whereby the sections of the drill pipe may be readily coupled together as the hole advances and the necessary electrical connections will be automatically established for lengthening the current conductor.

Still another object of the invention is to provide in a Well drilling system, drill pipe sections carrying current conductors with means at the two ends of each section, electrically connected with the conductor, whereby when one section is threadably coupled with another section an electric connection will be automatically established between the current conductors carried by the sections.

A lmore specific object of the invention is to provide in a well drilling system, a pipe line made up of a plurality of sections each carrying a current conductor, with a collector ring at one end of and concentric with each pipe section and supported in insulated relation therewith, and a terminal contact pin mounted in the opposite end of the pipe section and insulated therefrom and connected with the current conductor by which arrangement when one pipe section is threadably coupled with the other, the Contact pin of one pipe section will be brought into electrical connection with the collector ring of the other pipe section to electrically couple the conductors of the two sections.

The invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawings forming a part of the specification, with the understanding, however, that the invention is not to be understood as limited to the exact details of construction shown and described since obvious modifications will occur to a person skilled in the art.

In the drawings:

Figure l is a View in longitudinal section of a portion of a drill line, illustrating a portion of the present invention.

Figure 1a illustrates the lower or terminal portion of the drill line with a part of the lower pipe section and two motor units connected therewith.

Figure 2 is a longitudinal sectional View through two adjacent or cooperating ends of two pipe sections showing the same in separated relation and illustrating in detail the manner of electrically coupling the electric current conductors carried by the pipe sections.

Figure 3 is a view in elevation of the end of a pipe section having the current conductor ring embedded therein.

Figure 4 is a view in elevation of the opposite end of ak pipe section showing the current conducting contact which is designed for electrical connection with the conductor ring of the adjoining pipe section.

Referring now more particularly to the drawings the numeral I0 generally designates a portion of a drill pipe, made up of the individual sections Il, to the lower end of which pipe line is connected a bit operating or power unit generally designated I2 and made up of one or more l of the novel electric motors forming a part of the present invention.

As previously stated it is an object of the present invention to provide a power unit at the lower end of the drill pipe where driving power can be applied directly to the drill bit, with means for passing the drilling mud down the pipe line and through the power unit for discharge at the blades of the bit in the usual manner. Accordingly the power unit made up of one or more of the motors I2 is of the novel construction about to be described whereby this method of operation may be carried out.

Each of the motors l2 comprises a cylindrical shell or casing i3, one end of which, here shown as the upper end, is exteriorly reduced and screw threaded as indicated at 4, while the opposite end is interiorly reduced and screw threaded as indicated at l5. The reduced end portion Eil of one motor casing is therefore insertable into the interiorly reduced end of another motor casing so that two or more casings can be joined together in tandem.

The numeral i6 designates a top or cap for the upper end of a motor which cap is interiorly screw threaded as indicated at ll to receive the exteriorly reduced portion I4 when the top end of the casing is to be closed. This cap has the reduced tubular stem portion I3 which is externally tapered and screw threaded as indicated at I9, or threaded connection with the lower end or" the lowerinost pipe section l i of the drill pipe line.

The bore of the tubular extension i8 extends axially entirely through the cap and intermediate its ends it is of enlarged diameter as indicated at 28 to receive the hereinafter described end of the tubular motor armature. At its inner end the bore is of still greater diameter as indicated at 2i and this portion of greater diameter is interiorly threaded to receive a threaded packing gland 22 which maintains tightly around the inserted end of the armature shaft the .packing material 2.3.

t the inner end or" the threaded stern portion there is formed the encircling` shoulder 2e which opposes the attached end of the pipe section and this shoulder has mounted therein, in a suitable insulation material 25 which is embedded in the shoulder, a contact pin 2 which is electrically connected with an electric current conductor which passes through the cap to the interior thereof where it is attached to the mot-or coinmutator brush '23.

Adjacent to the opposite end of the motor casing which end, in the illustration here given, is the lower or bottom end, is a bearing collar 29 which supports a roller thrust bearing 3G for supporting the motor armature.

The armature of the motor is generally designated and at its two ends the body of the rmature merges with the reduced axially extending trunnions 32 and 33. Formed through the entire armature unit, that is, through the body and through the trunnions forming the end extensions of the body, is the boi'e or passage 35.-. The body of the armature carries the usual Ywindor electric current conductors, not detailed, and encircling the winding carrying portion of the armature is the usual eld unit or coil 35 n customary manner. The armature end nion has formed therein a key slot ivi coupling together a trunnion of one h a tr n oi another motor, in

for use inc-tor c is enlarged interiorly through portion of its length an is provided with va key or slot 3l which cooperates with a slot of an insert-ed trunnion 32 to receive-a'coupling hey 'The trunnion of the motor which is connected directly to the lowerniost pipe section li, extends into the portion 2Q of the bore of the cap it and is encircled by the packing gland which when tightened up compresses the packing around the inserted trunnion 32 so as to form a huid tight joint between the cap and the end of the armature.

The arn' ture trunnion 33 is held in the roller thrust bearing 3% in the manner illustrated so that when the motor is in operating position .1J-here the axis or" the armature is substantially vertical the weight of the armature will be borne by the thrust bearing.

The armature trunnion 32 carries the comis secured to the inner wall of the casing y illustr' EM this purpose the u,

mutator 39 and the wall of the motor casing" adjacent to the top end thereof has a brush supporting bracket 4E! which holds the brush 28 in proper position for contact with the commutator.

The cap I5 is provided with a removable plate 4| which covers the opening 42 which is provided for inspecting the brush and commutator and for adjusting the packing gland as may be required. Likewise the casing E3 adjacent to its lower end is provided with an inspection opening 43 which is normally closed by the plate 44. This opening is made use of for placing and adjusting the motor brush when two motor casings are joined together in the manner shown.

Extending lengthwise through each motor casing is a conduit 45. Through this conduit 45 is carried a current conductor 45 upon the lower end of which is connected the motor brush 4l. When two or more motors are connected in tandem as illustrated, the upper end of the conductor 45 is electrically connected with the commutator brush at the top end of the motor so that current can be carried from one motor to the next.

The numeral 43 generally designates a bottom cap or closure for the motor casing I3. This bottom cap has the exteriorly reduced and threaded portion 49 which is adapted for threaded engagement in the lower end of the casing. If only one motor is being used then the caps I6 and 48 will be coupled respectively with the upper and lower ends of the casing. If two or more motors are connected for use in tandem as illustrated then the cap l closes the upper end of the casing of the upper motor and the cap 43 closes the lower end of the casing of the lower motor, the adjacent ends of the motor casings being threadably coupled together to -form a continuous .casing housing two or more armatures. Likewise the armatures are coupled together as illustrated, the upper trunnion 32 of one armature extending into and being keyed to the lower trunnion of the overlying motor armature so that the armatures turn together as a single motor.

The lower cap 48 is axially bored as indicated at 5S to have extended therethrough the tubular coupling 5I, the upper end of which coupling extends into the enlarged lower end portion of the passage 34 of the lowermost armature, to which it is connected by a key 52 corresponding to the key 38. This coupling forms a connection hetween the Varmature of the lowermost motor and the drill bit 53. 'Such drill bit would, of course, be of tubular type so that the drill mud crculated through the aligned passages of the motor armature 34 will pass down through the coupling El and through and out of the discharge ports of the drill bit blades.

The outer end of the passage 5U of the lower cap 48 has threaded thereinto the packing gland 54 which maintains packing material 55 tightly around the lower end of the coupling 5! to prevent fluid getting into the motor casing.

For the proper conduction of current down the drill pipe line from section to section, each of the pipe sections El is of novel construction.

As shown each pipe section Il has 'extending therethrough a conduit 55 through which is run an electric current conductor 5l. One end of each pipe section is of enlarged diameter externally as indicated at 58 and this enlarged end portion 58 has extending therefrom the tapered coupling pin 59. There is thus formed around the coupling pin 59 the flat shoulder Si! in which ,is embedded the annular insulation body 61.

This insulation body carries a metal contact pin 62 which is electrically connected with an end of the current conductor 51.

The opposite end of the pipe section il is liliewise exteriorly enlarged as indicated at 93 and this enlarged portion 63 has formed therein the tapered socket @d for the reception of the coupling pin 59 oi another pipe section. There is thus formed around the outer end of the socket 64, the shoulder or end face 65 which is brought into opposed relation with the shoulder 60 when two pipe sections are joined together. This shoulder or end face 65 has embedded therein the annular insulation body 66 and this insulation body in turn has embedded therein the metal current conductor ring 6l which is of a diameter to be contacted by the pin 62 when the pin and ring ends of two pipe sections are joined together. The conductor ring 61 has electrically connected therewith the other end of the current conductor 57 thus electrically connecting together in each pipe section the pin and ring.

From the foregoing it will be readily apparent that with apparatus of the character herein disclosed electric motors may be directly coupled with the drill bit at the bottom of the well hole and at the lower end of the drill pipe and current can be passed down to the motors through the pipe sections without diiculty as it becomes necessary to add more sections to the drill pipe with progressive deepening of the hole, these sections may be added on in the usual manner without bothering about the establishment of electrical connections between the sections or between conduits carrying the current down to the motors, since the electrical connections will be automatically established with the joining of the ends of the pipe sections.

It will also be readily apparent that the power delivered to the drill bit may be increased as desired by joining together two or more oi the motors, the design of each motor being such that this connection of two or more motors may be made without difficulty and without requiring any parts other than those present as a necessary part of a single motor.

While the armatures of the motors have been illustrated as coupled together by keys, it is to be understood that the invention is not limited to this specic arrangement. If found feasible the armatures may be coupled together by screw thread fastenings or threaded couplings of the proper hand to assure the maintenance of such type of connection during the rotation of the armatures.

I claim:

1. In a well drilling apparatus, a motor unit designed to be operated at the lower end of a drill stem, comprising a relatively long housing incasing the'usual armature and field coils, the armature having axial supporting trunnions, a removable closure cap for each end of said housing, each of said closure caps having an axial passage therethrough, means for rotatably mounting one armature trunnion in a closure cap, means for coupling the last mentioned closure cap with an end of the drill stem, the armature and trunnions having an axial passage therethrough aligned with the passage of the said last mentioned closure cap and with the drill stem to receive drilling mud from the stem, a tubular coupling connected with the other armature trunnion and passing through the other closure cap, the tubular coupling being adapted to have a bit connected therewith, and

6 means for transmitting electric current to the armature within the housing.

2. In well drilling apparatus of the character described designed for connection with a tubular sectional drill stem, an electric motor adapted t@ be connected to the lowermost drill stem section, said electric motor comprising a housing having upper and lower ends, a cap closing the upper end of the housing, a cap closing the lower end of the housing, each of said caps having an axial passage therethrough, means for connecting the upper cap with the drill stem, an armature rotatably mounted in the housing and having an axial passage therethrough connected at its upper end with the passage of the top cap and the drill stem, a tubular coupling extending from the lower end of the armature through the bottom cap, the tubular coupling being adapted to have a bit connected therewith, and means for conducting electric current through the top cap into the housing to said armature.

3. Well drilling apparatus of the character stated in claim 2, wherein the coupling means between the caps and their respective ends of the housing is so constructed and arranged that upon removal of the cap from the lower end of said housing, the said lower end may be directly coupled with the upper end of a second housing, the said removed cap being transferrable to the lower end of said second housing, and means for directly coupling adjacent ends of the armatures of two coupled housings.

4. Well drilling apparatus of the character stated comprising in combination with a tubular drill stem, a bit operating tandem electric motor unit connected with the lower end of the stem, comprising two relatively long cylindrical housings, a screw thread coupling between the housings for maintaining the housings in coaxial relation, a top cap detachably connected with the upper end of the upper housing and having an axial passage therethrough, means detachably coupling the top cap with the lower end of the drill stem, a bottom cap detachably connected with the lower end of the bottom housing and having an axial passage therethrough, an armature rotatably supported within each housing, a field coil ingeach housing, each of said armatures having terminal trunnions, each of said armatures having a passage extending axially therethrough and through the trunnions, the trunnion of the armature in the uppermost housing being rotatably coupled with the top cap, the adjacent trunnions of the armatures oi the two housings being telescopically joined and coupled for simultaneous rotation, means for conducting electric current to the armatures of the two motors, a tubular coupling connected with the lower trunnion of the lowermost armature and extending downwardly through the bottom cap, and means for coupling a hollow bit with the lower end of said tubular coupling.

HARRY L. FEASTER.

REFERENCES CITED The following references are of record in the iile of this patent:

UNITED STATES PATENTS Number Name Date 1,666,461 Lord Apr. 17, 1928 2,105,091 MacKay Jan. 11, 1938 2,178,931 Crites et al Nov. 7, 1939 2,301,783 Lee Nov. 19, 1942 

